The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent the work is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Each year numerous children are referred by their pediatricians or primary care physicians to a cardiologist for further consultation upon detection of a heart murmur. A heart murmur is a sound occurring during a regular heartbeat cycle that is caused by turbulent blood in or near the heart area. However, a majority of the referrals are diagnosed as Still's murmur (an innocent heart murmur that occurs in childhood).
Still's murmur is a normal finding present in approximately 50-90% of healthy children. Still's murmur is most often present throughout the preschool and elementary-school years of a child, but may also be present in infants and older children. The incidence of Still's murmur exceeds the incidence of actual congenital heart defects (pathological murmurs) by over 50-fold. Still's murmur is characterized by a low-pitched pure tone that exists for a short duration between heart sounds and does not require any treatment. Furthermore, the occurrences of Still's murmur usually resolve by young adulthood.
However, the inability of primary care physicians (e.g., pediatricians) to distinguish between Still's murmur and a pathological murmur leads to a substantial number of specialist consultations and cardiac tests. The consultations and cardiac tests result in a high cost to the healthcare system and causes unnecessary anxiety for the patients and their parents. Furthermore, multiple studies have demonstrated that only cardiologists, among medical caregivers, can reliably make a distinction between pathological heart murmurs and Still's murmurs by using only a stethoscope, and that this skill does not improve in other medical caregivers with experience. Therefore, if the primary care physician (or other medical professional) detects a heart murmur that may indeed be a Still's murmur, he or she is most likely to refer the patient to a specialist for consultation and/or further testing, as the physician is unable to successfully diagnose the heart murmur as the benign Still's murmur.
Accordingly, there is a requirement for an apparatus and a technique for detecting Still's murmur in an efficient and reliable manner, such that unnecessary referrals of children with normal hearts to specialists are prevented.